Controller for arc-welding apparatus and the like.



L. P. COUL TER. CONTROLLER FOR ARC WELDING APPARATUS AND THE LIKE. APPLICATION FILED APR. 4. IBM- LQQLAQQ. Patented Jan. 14,1919.

ED STATES PATENT OFFICE.

LEONARD P. COULTER, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER- HAMMER MFG. 00., OF MILWAUKEE,

CONSIN'.

WISCONSIN, A CORPORATION OF WIS- CONTROLLER FOR ARC-WELDING APPARATUS AND THE LIKE.

Specification of Letters Patent.

Patented Jan. 14, 1919.

Application filed April 4, 1914. Serial No. 829,473.

To all whom 1'2 may concern:

Be it known that I, LEONARD P. CoUL'rER, a citizen of the United States. residing at Milwaukee. in the county of Milwaukee and State of lVisconsin, have invented new and useful Improvements in Controllers for Arellelding Apparatus and the like, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming" a part of this specification.

This invention relates to circuit controllers and is particularly applicable to controllers for electric arc welding apparatus.

The invention has numerous objects and advantages which will be best understood by reference to the embodiments thereof illustrated in the accompanying drawing, and now to be described.

In the drawing,

Figure 1 diagrammatically illustrates the electrode of an arc welding apparatus and one form of controller associated therewith and Fig. 2, is a view of similar character but showing a modified form of controller.

Referring more specifically to the drawing and to Fig. 1 thereof, the same shows welding electrodes 1 and 2 and circuit controlling means to regulate the arc therebetween, said controlling means including parts functionin automatically upon relative movement 0 said electrodes.

The controlling means includes two sets of resistances for the electrode circuit, which will be termed starting and steadying resistances. The starting set includes a fixed resistance r and an adjustable resistance 2* while the steadying set includes a fixed resistance 1' and an adjustable resistance 1*. The latter set of resistances, save for adjustment, is permanently included in circuit while the former set is adapted to be excluded from circuit for Welding and to this end is provided with an electromagnetic control switch 3. The switch 3 in turn is The controller operates and functions as follows: When the electrodes are moved toductor 7 through both windings of relay switch 4 by conductor 8 through the Winding of relav switch 5, by conductor 9 through the starting resistance r and any desired part of the resistance r, by conductor 10 through any desired part of the steadying resistance r and thence through resistance 1' to line Circuit is thus completed by and through the electrodes with the voltage and current reduced to the desired degree by the several resistances.

Also, at this time circuit is closed through the windings of the relay switches 4 and 5 and both of said switches are set or adjusted to respond immediately. These relays are in series in the energizing circuit of switch 3, the switch 4 being normally open and the switch 5 being normally closed. Thus when the relay switch 4 closes it tends to energize switch 3 but is precluded from so doing by response of the relay switch 5. In conse' quence the electrode circuit is unaffected by the response of switches 4 and 5.

When. however, the electrodes are separated to draw an arc therebet-Ween the current in the electrode circuit is decreased and when decreased to a predetermined value effects the release of relay switch 5. Said switch thereupon returns to normal position thereby completing the energizing circuit of the switch 3 from line L by conductor 11 through relay switch 4. by conductors 12 and 13 through the winding of switch 3, by con ductor 14 to line L.

Switch 3 thereupon responds to complete circuit from winding 4" of relay switch 4, by conductor 15 through said switch 3, by conductor 16 to conductor 10. It thus shortcircuits the starting resistances r and 1" whereby the current delivered to the electrodes is increased for the welding operation. During such operation the current may be regulated by the variable resist ance 1' The connections established by switch 3 also short-circuitv the winding of relay switch 5 and the operating winding 4. of relay switch 4. Thus both switches have their menace operatingwindings rendered ,inert. The switch 4: however is maintained in closed position by its holding coil 4:" which is designed to carry the full current of the electrode circuit.

It will thus be observed that the controller provides for automatic control of the electrode circuit upon relative movement of the electrodes and that the current relaycswitch 5 automatically times the operation ofthe switch 3 to insure inclusion of the starting resistances for the desired period.

Further it will be observed that the relay switch 4 provides for connection of the winding of switch 3 directly across the supply lines and thus renders said winding independent of the voltage fluctuations of the electrode. circuit. This is highly desirable in many instances but where such provision is not essential the relay switch 4 mav be omitted and the controller thereby simplified as shown in Fig. 2;

Referring now to Fig. 2, the same shows all of the elements of Fig. 1 with the exception of the relay 4 and also shows the same circuit connections for all of said elements except the operating winding of the switch 3. In this instance the operating winding of the switch 3 instead of being connected across the lines is connected between the electrode 2 and the line L. Thus the electrodes perform the function of the relay 4 of Fig.

1, namely in completing the energizing circuit of switch 3 subject to retardation by the current relay 5 which is designed to respond in advance of switch 3. This controller accordingly operates and functions in substantially the same manner as the controller illustrated in Fig. 1.

More specifically describing the modifications in circuit connections, the switch 3 is connected directly to electrode 2 by conductor 17 and its energizing circuit extends from conductor 17 by conductor 18 to relay switch 5. With these exceptions the connections are precisely like those of Fig. 1.

The controller of Fig. 2 is also advantageous in that it provides for automatically reducing the flow of current through the winding of switch 3 upon response of said switch. That it so functions will be ap-- parent from the fact that prior to closure of said switch its winding is paralleled by all of the resistances whereas after its closure the starting resistances are shortcircuited leaving only the steadying resistanccs in parallel with said winding.

What I claim as new and desire to secure by Letters Patent is 1. In a welding system, in combination, welding electrodes, power connections therefor, an electro-responsive power controller, and electro-responsive means connected in series with said electrodes to time the response of said power controller, said power controller having connections, insuring a breakin of its circuit upon interruption of the c cctrodc circuit.

2. in a welding system, in combination,- weldin electrodes, power connections therefor, e ectro-rcsponsive power controlling means, and means connected in series with said electrodes to time the response of said power controlling means, said power controlling means upon responding rendering said timiu r means inert and in turn being deenergizm upon interruption of the electrode circuit.

3. In a controller of the character set forth, in combination, a regulating device for the controlled circuit, electro-responsive means tending to efle'ct operation of said device upon closure of said circuit and a current relay responsive to the current of said circuit to time the operation of said electro-responsive device, said device upon operating rendering said relay inert.

4. In a controller of the character set forth, in combination, electro-responsive means for regulating the controlled circuit, two switches controlling the energizing circuit of said means, one of said switches being normally open to break the circuit of said means and the other being normally closed, and operating windings 1n the controlled circuit one for each of said switches.

5 In a controller of the character set forth, in combination, electro-responsive means for regulating the controlled circuit, and two electro-responsive switches controlling the energizing circuit of said means, one of said switches beingnormally open and having an operating winding and a retaining winding in the controlled circuit and the other of said switches being normally closed and having an operating winding in the controlled circuit.

6. In a controller of the character set V forth, in combination, electro-responsive means for regulating the controlled circuit,

' two electro-responsive switches controlling the energizing circuit of said means, one of said switches being normally open and having an operating wmdlng and a retaining winding in the controlled circuit and the other of said switches being normally closed and havin a winding in the controlled circuit, and circuit connections whereby the operating windings of bothof said switches are excluded from circuit upon response of said electro-responsive means.

7. The combination with the electrodes of a welding apparatus, of a circuit therefor having its continuity controlled thereby, electro-responsive means for regulating said circuit, said means having an energizing circuit independent of said first mentioned circuit, two switches governing said energizin circuit one being normally open to break t e energizing circuit and the other being normally closed, and operating windlngs for both of said switches energized upon completion of said electrode circuit, and the winding of said normally closed switch releasing the same upon a predetermined reduction in the current flowing through said electrodes.

8. The combination with the electrodes of a welding apparatus, of a circuit therefor havin its continuity controlled thereby, a norma ly open switch having an operating winding and a holding winding in series with said electrodes, a normally closed switch having an operating winding in series with said electrodes and adapted to release at a predetermined current value, and an electro-responsive device governed in its operation by said switches, said device upon responding varying the electrical conditions in said electrode circuit and excluding from circuit the operating windings of both of said switches.

9. In a welding system, in combination,

electrodes, a power circuit therefor, a resistance normally included in said circuit, elec- LEONARD P. COULTER. Witnesses TEKLA BOST, ELIZABETH EBERLY. 

